During her fifth year at Hogwarts Minerva was quite the efficient student. She preformed her Prefect duties efficiently and effectively while maintaining her position on the Quiditch team as a chaser. Not only did she have time to study for her Newts and achieve all Os, but she also managed to stop by Dumbledore's office every few weeks.
Although his answer was always the same, Dumbledore didn't mind her frequent visits and being reminded of his promise to teach her.
At first she didn't stay longer than a few minutes. She would politely refuse a lemon drop and then ask, "Professor, have you reconsidered teaching me how to become an animagus?"
As months passed her trips to Dumbledore's office had lasted longer and longer. She might ask about the current assignment or something to do with a book she was reading. Then they would discus transfiguration articles or a particular theory for hours while sipping tea or hot chocolate on occasion.
The first few weeks she held some hope that he would reconsider, but that hope slowly faded over a year's time, until on some visits she didn't even mention animagus training. She still enjoyed engaging in academic discussions with someone who had a thirst for knowledge like herself and wouldn't call hare a bookworm or worse.
While she enjoyed visiting with Professor Dumbledore, the summer vacation was fast approaching. She wasn't looking forward to months away from Hogwarts without using magic, and without a large library to entertain her. But she most especially would miss those lively discussions and debates with Professor Dumbledore. She would miss his company the most (although she didn't want to admit it). Somehow she had labeled him as a friend, her best and only friend here at Hogwarts.
She was standing on the platform looking up at the Hogwarts Express, wishing that she didn't have to leave when she heard someone say her name.
She turned around and behind her was Professor Dumbledore, "Well, Miss McGonagall, you look as if the train has caused you some great tragedy. I hope that is not the case, for I particularly like our Hogwarts Express and would hate to see anything happen to it," he finished looking rather too happy.
Minerva returned a rather forced smile saying, "I guess I just don't want to leave Hogwarts this year."
"Cheer up then," he said. "Time away from Hogwarts will make you enjoy next year all the more, or as muggles say, "Absence makes the heart grow fonder.""
She couldn't help but smile thinking of all the things she would be "fonder" of next year, as Dumbledore had very similar thoughts.
Most all of the students were already on the train. Looking back at the train, she said, "I will try to remember that."
"Have a relaxing summer," he said as he walked her to the train door.
Smiling back, she got on the train and found a seat near the window. Looking out she saw that Dumbledore was looking back towards the castle but she had forgotten something. She leaned out the window, "Professor Dumbledore," she practically yelled.
He turned back and she continued, "Have you reconsidered?" It was all she had to say and he knew what she meant. The answer was still, not yet, but he didn't need to say it anymore, so he just smiled and waved as the train pulled away from the platform.